Portuguese name

A Portuguese name is typically composed of one or two given names, and a number of family names (rarely one, but often two or three, seldom more). The first surname(s) are usually the mother's family surname(s) and the final surname(s) are the father's family surname(s).

For practicality, usually only the last surname (excluding prepositions) is used in formal greetings or in scientific papers indexing. But, in a list of people, the first given name, not the surname, is used for alphabetical sorting. A married woman may add her husband's last surname(s) to the end of her own name, but this is not mandatory and increasingly less common. The same may happen with men, though this is extremely rare.

The Portuguese naming system is quite flexible. Portuguese law establishes the need for a child to have at least one given name and one last name (surname) from one of the parents, although having only one last name is now very rare. The law also establishes the maximum number of names allowed: up to two given names and four surnames. This restriction is generally not enforced and it is not uncommon to have more than 4 surnames.

Historically it was common practice for daughters to be given the mother's family name and sons to be given their father's. For example, Vasco da Gama married Catarina de Ataíde. They had six sons who bore the surname da Gama, and one daughter who had the surname de Ataíde. Even now, among the older population, it is not unusual to find siblings with completely different combinations of surnames.

To add to this basic pattern, a second given name, or other paternal or maternal surnames are optional, up to the aforementioned limit of two given names and four surnames. Both limits are sometimes not respected, especially among the former aristocracy. Usually, the maternal surnames precede the paternal ones, but the opposite is also possible. If the father is unknown, or he has not acknowledged the child, only the mother's family name(s) is/are used. A child can receive surnames from his/her parents' ancestors, even if those surnames are not part of the parents' names, under the condition that the parents prove those names were used by their ancestors.

Most Portuguese-speaking people use only their last surname (usually the paternal one) in their daily and professional life. The regular usage of a middle surname or of a combination of two surnames is also widespread.

Complete names are formed generally as in Western Europe, i.e., by first names, followed optionally by one or more middle names, followed by the mother's family surname, followed by the father's family surname. Examples:

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